Overall the car is significantly quieter than similar midsize cars. Road isolation is excellent without removing road feel altogether.
The trunk this car has is one of the most usable and well designed I've ever experienced on a car of this size class. I've successfully fit 4 full size suitcases and two small duffel bags into the trunk. In addition, I've also filled it to the brim with very dense items, including cases of water and many other large stack-able foodstuffs, and was very pleased to find not only how much I was able to fit size wise, but how well the vehicle handled the extra weight in the rear.
Safety & braking
This car's safety ratings are more than acceptable, which was a large part of my purchasing decision. In addition, the brakes have a very logical feel to them in many different conditions.
The vehicle does apparently have a stability control system in addition to traction control with ABS. Recently during a long trip (3500 miles), during which I went through blizzard conditions (including completely packed icy roads, slush and deep wet snow). I frequently saw the indicator lights for stability control interaction flash on the dash without actually noticing any sort of interference with the action I was attempting. This both instilled confidence but also induced worry about its proficiency.
Ford upgraded the tires on the 2011 and later Fusion 17" wheels from the Michelin Pilot HX MXM4 tires once standard 2006-2010 to the newer Michelin Energy Saver A/S. The Energy Saver A/S tire is significantly quieter, much longer lasting (I've personally witnessed with proper care, able to attain 70,000 miles), and more adept at being an all season, low rolling resistance tire. However, while being significantly better than the Pilot, it's not one of Michelin's best offerings. I opted to replace the tires at 40k miles (with plenty of tread remaining) with a set of Michelin's Primacy MXM4. This, by FAR increases the car's wet traction abilities, including snowy and icy conditions.
Front seat support & comfort
The front seats are very comfortable, and provide very adequate support for long trips. Side support isn't the very best for hard cornering though.
My primary complaint with the vehicle as a whole definitely comes down to fuel economy. I've owned several other vehicles that should generally be less economical that actually are almost the same. My primary example is one of my previous cars, a supercharged 1996 Buick Park Avenue. Overall average fuel economy with that Buick was about 20, with 70% city driving. Overall fuel economy with my V6 3.0 Fusion is...about 20 with the same driving conditions. Its to be noted that car's posted fuel economy figures for highway driving aren't really attainable. 240 HP in a midsize car isn't bad...but I sometimes wish I'd gotten the 4 cylinder.
Driving position & visibility
I stand at 6'2". Not overly tall for a male. In my car, with the seat height all the way down, my hair is touching the ceiling. The biggest issue with that is that the rear view mirror does limit my overall visibility with it being in my line of sight.
In addition to this, even sitting at my level, as high as possible, it is extremely difficult to judge where the front and back of the vehicle end. Side to side judgement is very predictable however.
Overall cornering of the vehicle is more what you would expect from the MKS or Milan. It's not extremely composed as you'd expect from a car similar to this, or even you'd expect from driving this car on a normal basis. I do understand that the handling is limited to preserve ride quality, which is very successful, but the car does have a somewhat unpredictable limit when pushed hard in certain situations. One example was an exit ramp from a freeway that I entered two or three times more quickly than it was designed for, and a hard combination of stopping and turning greatly upset the normally composed feeling you get from the suspension, steering and chassis.
The transmission in this car is a nightmare of unpredictability. It's very obvious that the machine itself is sound, but the electronic control and programming, as well as its adaptive features are a bit under-engineered. I've had the transmission controller re-flashed with the latest Ford has available for this transmission, but the improvements, while present, were very small. I hope that it doesn't affect its overall reliability, which sometimes feels questionable.
I bought this car after renting one in MA and truly loving it right away with its quietness, road isolation, comfort, fuel economy (4 cyl), and predictable handling in icy conditions. Its huge trunk definitely was a sweet bonus as well.